Purification of hydrocarbons by extraction with phenolic materials



May 17, 1960 R. w. HOYER PURIFICATION oF HYDRocARBoNs BY EXTRACTION WITHPHENOLIC MATERIALS Filed March 15, 195@v United States Patent [OPURIFICATION F HYDROCARBONS BY EXTRAC- A TION WITH PHENOLIC MATERIALS yRalph W. Hoyer, Aldan, Pa., assignor to` Gulf `Oil Corporation,Pittsburgh, Pa., a vcorporation of Pennsylvania Y Application March'is,1956, serial Rijst/1,327V 7 claims. (amos-324) This invention has forits object to provide improved procedure -for 'separating phenolicmaterial from aqueous solutions and in particular to a combination ofprocedural f' 2,937,139 ce Patented May 17, 1960 taining part or all ofthe residual components of the crude may be utilized. On the other handdistillate oils may be employed as long as they are largely composed ofhydrocarbons boiling above the gas oil range. I prefer to utilize alubricating oil stock or an oi test lubricating oil which is to bepurified by extraction with a" phenolic material. In this way thephenolic materiall removedV from the solid adsorbent and dissolved inthe lubricating roil stock is 'utilized in the subsequent extraction ofthe lubricating oil stock with phenolic material. Experimental /dataindicate that the higher boiling or higher API gravity oils are mostsuitable for removing adsorbed .phenolic materials from the solidAadsorbent. The hydrocarbon oils utilized should be primarily composed ofhydrocarbons boiling between about 100 C. vto 350 C. at.0.1 mm. Hgpressure. When lubricating oil stocks are used, they should be composedprimarily of hydrocarbons which boil between about 200 and 275 C. at 0.1mm. Hg pressure.k It is advantageousto use a hydrocarbonwhich has beendewaxed. My invention' also may be carried out using synthetichydrocarbons boiling of phenolic-materials are obtainedinother`industrial processes and the recovery of the lphenolic materialstherefrom also is a problem. Recovery is desirable not only because ofthe value of the phenols but because of the necessity for avoidingpolution of streams.

This invention has for its object to provide improved procedure forextracting hydrocarbon fractionsv with phenolic materials. Another'object is to provide improved procedure for separating phenolicmaterials from aqueous solutions containing them; Another object is toprovide .a combination process whereinv phenolic materials may berecovered from aqueous solutions and econorru'cally utilized inextraction of hydrocarbons with phenolic materials. Another object is toimprove-the state of the art. Other objects will appear hereinafter;4

in the rangesv given above.

' The solid adsorbent employed to adsorb the'phenolic material fromaqueous solutions may be any solid material having a tine pore-likestructure such as fullers earth, bauxite, Florida-Georgia earths, acidtreated bentonite, acid treated natural silica-alumina crackingcatalysts, silica gel, activated carbon, etc. 'I prefer to employ aspent or Y partially spent solid adsorbent whichhas been previouslyThese and other objects are 'accomplished bymy in# f v vention whichincludes contacting an aqueous'f solution of` phenolic material with asolid adsorbent whereby vthe solid adsorbent takesfup or adsorbs'asubstantial amount of the phenolic material from the aqueous solution,draining the water from the solid adsorbent and contacting the solidadsorbent with ak hydrocarbon oil composed primarily of hydrocarbonsboiling above gas oil whereby the hydrocarbon oil dissolvesl or removesa substantial amount of the phenolic material from the solid adsorbent.I have discovered'that such hydrocarbons are capable of removing largeamounts Yof phenolic materials from an adsorbf,

enton which they have been'l adsorbed fromiaqueous solutions. ,f

- Inthe following examples and description I have *set forth several ofthe. preferred embodiments of my invention, but it is to be understoodthat they are given by way `ofillustration and not inlimitation thereof.

. lThe hydrocarbon utilized to remove the adsorbed phenolic material'fromthe solid adsorbent may be any hydrocarbon oil boilingrabove gasoil. YThus a liquid vpetroleum fractionV boiling above gasoil, whetherlparaffnic, naphthenic and/or asphaltic in nature and whether containingresidual and/or distillate'vcomponnts, may be employed. For instance aliquid reduced crude conempioyed for decolorizing, catalytic cracking,etc. and

which has been regenerated one or more times as described in U.S. patentapplication Ser. No. 5 18,5 33, filed June 28, 1955, Carlos B. Rios.

The aqueous solution from which the phenolic ma terials are to be'recovered may be derived from any source. In the purification ofvarious petroleum fractions, itis known to extract with phenol or otherphenolic materialssuch as cresol, wood tar acids, etc. For instancephenol is used toV extract lubricating oilY stocks to improve viscosityindex, oxidation resistance and to reduce carbon and sludge formingtendencies. Steam is usedto remove thephenol from the raiiinate andextract in such processes andas a result water containing phenol Y 1sobtained. -Myi'nvention'is applicable to the separa-` tion of phenolsfrom such aqueous solutions. .As another example, the Duo Sol process'for purifyinglubrioating oil-sbyextraction with a double solvent such as'propane andwood tar acids may be mentioned. In this process one ormoreaqueous streams containing phenolic materials desired from the Woodtar Aacids are obtained and may be kcontacted with a solid adsorbent torecover thesel phenolic'materials. The same Duo Sol process is also'carriedv out with a mixture ofV phenols and cresols instead ofk the woodtar acids. petroleum fractions, oxidation products are formed or arepresent in the charge stock and these oxidation prod- Vucts are to. aconsiderable extent phenolic in nature.

' operations suchas therrnanufacture of phenols, aqueous solutions of.phenolic materials are obtained and their recovery maybe accomplished'byutilizing the principlesV In catalytic cracking of of my invention. Myinvention is of particular value in connection with the removal ofphenolic materials from aqueous solutions containing them in relativelysmall amounts such as about 40 to about 12,000 parts per rnillion.However, my invention is applicable to the removal of phenolicsubstances from all aqueous solutions, and it Will be understood thatlower or higher concentrations of phenolic materials in water may berecovefed.

The aqueous solution containing phenolic substance may be contacted withthe solid adsorbent in any desired manner. Thus the solid adsorbent maybe used in the form of iilter beds and the water simply filtered orpassed through these filter beds. Also the solid adsorbent and the watermay be mixed with each other and the solid adsorbent then separated fromthe water by settling. This last method of operation may be advantageouswhere the the solid adsorbent is in such a finely divided condition thatltering through a bed of the iinely divided material would beuneconomically slow. Contacting of the aqueous solution with the solidadsorbent is continued until the adsorption of phenolic materials ceasesor decreases to an unsatisfactory degree. This can be detected byanalysis of the eiuent water. Thus the phenolic content of the eiuentWater Will start to rise. The operation is then terminated and the waterdrained from the adsorbent. The solid adsorbent is then contacted withthe hydrocarbon oil. This contacting may take place in the same manneras the contacting with the aqueous phenolic solution. The hydrocarbonoil is then drained from the adsorbent and the adsorbent is washed witha lower boiling solvent for the hydrocarbon oil such as naphtha,benzene, liquid propane, etc. The absorbent is then steamed to removethe solvent adhering to the washed solid adsorbent and the solidadsorbent may be again contacted with an aqueous solution containingphenolic materials.

In order to have a continuous process it is advantageous to utilize twocontacting towers or chambers. One of these will be undergoingregeneration while the other is on stream. When the on-stream towerbecomes saturated with the phenolic substance, the ow of aqueousphenolic solution will be switched to the other tower which in themeantime will have been regenerated or put in condition for adsorptionof additional phenolic suhstances as described above. The spent solidadsorbent chamber then will be regenerated while the adsorption is goingon in the other tower.

In the accompanying drawing I have illustrated diagrammatically,apparatus in which a preferred modification of my invention may becarried out. Referring to the drawing, a charge stock suitable formanufacture of lubricating oil is introduced via conduit 2 into a DuoSol type extractor 4 where it is extracted with a double solvent(propane and phenolic material such as wood tar acids) in known manner.The two solvents are passed countercurrently to each other and thepropane serves to reject asphaltic vmaterials and to dissolve parainicmaterials of high lubricating value. The raflinate, i.e. propane anddissolved parafiinic materials, is treated in propane recovery unit 6 toseparate the paraflinic lube oil components from the propane. The lubeoil components are removed through conduit 8 and the liquid propane isreturned to propane storage tank 10 via conduit 12. The extract phase,i.e, the tar acids and the dissolved asphaltic materials is removed fromextractor 4 via conduit 14 and is treated in tar acid recovery unit 16to separate asphaltic materials (which are removed via conduit 18 fromthe tar acids. The tar acids are stripped with steam and the purifiedtar acids are returned to tar acid storage 20 through conduit 22. Thecondensed stripping steam containing dissolved tar acids is passedthrough conduit 24 to liquid propane storage 10.y Propane and tar acidsutilized in the Duo Sol extractor are withdrawn from storage tanks 10and 20 via conduits 28 and 26 respectively.

The waste water containing phenolic materials in storage tank 10 iswithdrawn through conduit 30 and introduced into percolation iilter 32through valve 33 and conduit 34. Percolation filter 32 is illed withpellets, pieces or particles of solid adsorbent such as Florida clay.The waterV flows through the bed of solid adsorbent and phenolicmaterials are adsorbed. At this stage of operation valves 36, 38, 40,42, 44 and 46 controlling ow through conduits 48, 50, 5256, 58 and 60respectively are closed. The water relatively free of phenolic materialsis removed from filter 32 via conduit 62 by pump 66 and sent to disposalthrough conduit 68.

When the adsorptive power of the clay in iilter 32 is reduced ,asevidenced by increase of phenolic materials in the water owing throughconduit 68,V valve 33 is closed and Water draining from filter 32 isremoved by pump 66. Thereafter operation of the pump is terminated andvalve 64 is closed. Valves '38 and 42 are then opened to permithydrocarbon oil to flow through conduits 50 and 34 into lter 32. Thehydrocarbon oil then flows through valve 42, conduit 56 and thence toextractor 4 with fresh charge. During passage through filter 32 thehydrocarbon oil dissolves a `substantial portion of the phenolicmaterial adsorbed by the clay during the pre- Vvious operation. When theamount of phenolic material removed by the hydrocarbon oil solventsubstantially decreases, valve 38 is closed and after the hydrocarbonoil content of filter 32 has been drained, valve 42 is closed. Valves 40and 44 then are opened and naphtha is passed through lter 32 to dissolveand remove the hydrocarbon oil retained on the surface or held in thepores of the adsorbent clay. This naphtha is removedthrough conduit 58and is sent to naphtha storage or redistilled for re-use. After thehydrocarbon oil has been largely removed from filter 32, valve 40 isclosed and after naphtha has drained from lter 32, valve 44 is closed.Then valves 36 and 46 are opened and stripping steam is introducedIthrough conduit 48, valve 36, and conduit 34 and is removed via valve46 and steam condenser 70. The steam condensatefrom condenser 70 isintroduced into yseparator 72. Steam passing through fil-ter 32 removes,residual naphtha which is separated in naphtha separator 72 and removedthrough conduit 74. Waste water is removed from separator 72 by pump 76and introduced into waste water line V68.

EXAMPLE In the following two-experiments an olf test neutral lubricatingoil anda 200vviscosity refined neutral oil having the characteristicsshown in TableI were used as solvents -to remove phenols from a solidadsorbent. These phenols were absorbed on the solid adsorbent from waterfrom the propane storage tank of a Duo-Sol extractor used to prepare ahydrocarbon oil from a reduced crude. This Water was condensed fromstripping vsteam used t0 strip the tar acids used in the Duo-Solprocess. The solid adsorbent was in the form of particles (1640 mesh)and was a decolorizing clay which had been repeatedly used to decolorizea lube oil in the prepmation of Bright Stock.

Table I Oil Test 200 Neutral Neutral Gravity, API 26.4 29. 2 Viscosity,SUV. Sec. 100 F 8 224 Color, ASTM Union..-- 3 5 dil. 3. 5 CarbonResidue, Percen 0. 34 0.01 Phenols, Percent trace trace Overpoint at 760mm. Hg Pressure, C 370 345 Overpolnt at 0.1 mm. Hg Pressure, C... 127111 Point at 760 mm. Hg Pressure, C.. 615 430 95% Point at 0.1 mm. HgPressure, C 326 184 The results of these two experiments are given inTable II.

Table Il Duration of Run llourso. 10 13 guter Ratei ldiitou. 1re/Hr0.316 0.316

c o e z apolg 18 18 Cu. Ft... 860 860 Total Flow Phenolic-Type TotalFlow Phenolic-Type v Compounds Compounds Wt. Wt. Percent Percent Bbl.Lbs. P.p.m. Lbs. of Bbl. Lbs. P.p.m. Lbs. ol'

. Phenols Phenols Charged Charged to Filter: l Y- 1 Challter fromPropane Tank 64. 5 22, 550 9, 600 216. 5 0. 0V 83. 8 29, 315 9, 600 281.4 100.0 Off-Test Neutral Oil 83. 8 26, 250 tr. 0. 0 200 ViS. Neutral Oil64. 5 19, 840 tr. .0

Total- 178. 0 58, 340 216. 5 100. 0 167. 6 55, 565 281. 4 100.0

Eiu nt from Filter: f

Vgater from Propane Tank 64. 22, 550 4, 200 94. 7 43. 8 83. 8 29, 315 4,200 123.1 '43. 8 Ott-Test Neutral Oil. 83. 8 26, 250 3, 186` 83. 6 .29.7 200 Vis. Neutral Oil 64. 5 19, 840 2, 530 50. 2 23. 2 Naphtha 13. 0 3,36 3, 600 12. 1 5. 6 Steam Condens'ate 36j. 0 12, 590 5. 2 0. 1 0. OPhenolsleiton Clay- 59.4 27.4 74.7 26.5

Total 178.0 58, 340 216. 5 10050` 167.6 55, 565 281.4 100. 0

Phenols Removed by Clay 121.8 56. 2 158.3 56. 3 Phenols Removed fromClay 1:

By O-Test Neutral Oil. 83.6 52. 8 By 200 Vis. Neutral Oil- 50. 2 41. 2By nnnhtlm 12. l 10. 0 By steam. 0. 1 0. 1

1 Based on phenols removed by clay as 100%.

The data in Table II show that both lube oils were quite effective inremoving adsorbed phenolic materials from the solid adsorbent. Thesedata also show that the oi test neutral oil was more effective inremoving phenolic materials than the 200 viscosity neutral oil, i.e.'the off test neutral oil removed 52 percent of `the adsorbed phenolswhile the 200 viscosity oil removed 41 percent.

I claim:

1. The process for recovering phenolic material from waste water whichcomprises contacting the waste water with a solid adsorbent whereby asubstantial amount'of the phenolic material in thewaste water isadsorbed by the solid adsorbent, draining water from the solid adsorbentand removing a substantial amount of the adsorbent and removing asubstantial amount of the adsorbed phenol from the solid adsorbent bycontacting.v the solid l adsorbent while it still retains water,excepting that water which drains therefrom by gravity, wi-th alubricating oil fraction composed primarily of hydrocarbons having aboiling point between about 200" and 275 C.

at 0.1 mm. Hg.

2. The process for recovering ,phenolic material from waste water whichcomprises contacting the waste water with a solid adsorbent whereby asubstantial amount of the phenolic material in the wastev water isadsorbed by the solid adsorbent, draining water from the solid adsorbentand removing a substantial amount of the adsorbed phenol from the solidadsorbent by contacting it with a j liquid petroleum fraction primarilycontacting the solid adsorbent while it still retains Water, exceptingthat water which drains -therefrom by gravity, with an off testlubricating oil composed primarily of hydrocarbons boiling between about200 and 275 C. at 0.1 mm. Hg.

3. Thefprocess for separating phenolic material froml I dominantly inthe lubricating oil boiling range whereby the` phenolic materialadsorbed on theV solid adsorbent is dissolved in the petroleum fraction,withdrawing said petroleum fraction from the adsorbent, treating thesolid adsorbent containing adherent petroleum `fraction boiling in the'lubricating oil range with a lower boil-ing petroleum fraction wherebythe petroleum fraction boiling in the lubricating oil range is dissolvedtherein, drain.

4. In a process for purifying a lhydrocarbon lubricating l oil stock byextraction with a phenolic material in which process water is obtainedcontaining a small amount of phenolic material, the improvement whichcomprises contacting the water containing a small amount of phenolicmaterial with a solid adsorbent whereby the solid adsorbent adsorbs asubstantial amount of phenolic material, draining water from the solidadsorbent, contacting the adsorbent with a hydrocarbon lubricating oilstock whereby a substantial amount of the phenolic material is dissolvedin the lubricating oil stock, withdrawing the lubricating oil stock fromthe adsorbent and then extracting the lubricating oil stock containingthe dissolved phenolic material with a larger amount of phenolicmaterial in order .to purify the lubricating oil stock contain ing thephenolic material dissolved from the solid adsorbent. f

5. In a process for purifying a hydrocarbon lubricating oil byextraction wtha phenolic material in which process -Water is obtainedcontaining a small amount of phenolic '70 material, the improvementwhich comprises' contacting the water containing la small amount ofphenolic material with a solid adsorbent whereby the solid adsorbentadsorbsv a substantial amount of phenolic material, draining water fromthe solid adsorbent, contacting the adsorbent with an oi testhydrocarbon lubricating oil Iwhereby a substantial amount of thephenolic material is dissolved in the lubricating oil, withdrawing theoi test lubricating oil from the adsorbent' Yand thenextracting theV offtest lubricating oil containing the dissolved phenolic material with alarger amount of phenolic material in order to purify the oif testlubricating oil.

6. In a process for purifying a hydrocarbon lubricating oil byextraction with a phenolic material in which process water is obtainedcontaining a small amount of phenolic material, the improvement whichcomprises contacting the water containing a small amount of phenolicmaterial with a solid adsorbent whereby the solid adsorbent adsorbs asubstantial amount of phenolic material, draining water from the solidadsorbent, contacting the adsorbent with an off test hydrocarbonlubricating oil whereby a substantial amount of the phenolic material isdissolved in the off test lubricating oil, withdrawing the off testhydrocarbon lubricating oil from the solid adsorbent, washing the solidadsorbent with a lower boiling hydrocarbon, withdrawing the lowerboiling hydrocarbon from the solid adsorbent, steaming the solidadsorbent, re-using the solid adsorbent to -remove phenolic materialfrom water, and extracting the oi test lubricating oil containing thedissolved phenolic material -with a larger amount of phenolic materialin order to purify the orf test lubricating oil.

7. In a process for purifying a hydrocarbon lubricating oil stock byextraction with a phenolic material in which process water is obtainedcontaining a small amount of material with a solid adsorbent whichhasbeen substan'" phenolic material, the improvement which comprisescontacting the water containing a small amount of phenolic tially spentin a decolorizing process whereby the spent solid adsorbent adsorbs af'sub's'tantial amount of Vphenolicl material, draining water from" thespent solidadsorbent, contacting lthe spent adsorbent with an'ot'te'st,heavy hydrocarbon lubricating oil stock whereby a substantial amount ofthe phenolic material is dissolved in the lubricating oil-stock,withdrawing the oit' test heavy hydrocarbon lubricating oil stock fromthe solid adsorbent, and then extracting the oi test lubricating oilstock containing the dissolved phenolic material with a larger amount ofphenolic material in order to purify the oi test lubricating oil stock.

References Cited in the tile of this patent UNITED STATES PATENTS Y,

UNITED STATES PATENT OFFICE CERTIFICATE OE CORRECTION Patent No.2,937,139 May im 19'60 Ralph Wu Hoyer It is herebr certified vthat errorappears in the -printed specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 2, line 50, for "desired" read M derived ma; lcolumn 4, line 52,for "absorbed" read adsorbed column 57 lines 49 and 50, strike out "theadsorbent and removing a substantial amount of; lines 63 and 64 strikeout "cont-.acting it with a liquid petroleum fraction primarily".

Signed and sealed this 18th day of October l901 (SEAL) Attest:

KARL H. AXLINE ROBERT C. WATSON Attesting Oficer Commissioner of Patents

1. THE PROCESS FOR RECOVERING PHENOLIC MATERIAL FROM WASTE WATER WHICHCOMPRISES CONTACTING THE WASTE WATER WITH A SOLID ADSORBENT WHEREBY ASUBSTANTIAL AMOUNT OF THE PHENOLIC MATERIAL IN THE WASTE WATER ISADSORBED BY THE SOLID ADSORBENT, DRAINING WATER FROM THE SOLID ADSORBENTAND REMOVING A SUBSTANTIAL AMOUNT OF THE ADSORBENT AND REMOVING ASUBSTANTIAL AMOUNT OF THE ADSORBED PHENOL FROM THE SOLID ADSORBENT BYCONTACTING THE SOLID ADSORBENT WHILE IT STILL RETAINS WATER, EXCEPTINGTHAT WATER WHICH DRAINS THEREFROM BY GRAVITY, WITH A LUBRICATING OILFRACTION COMPOSED PRIMARILY OF HYDROCARBONS HAVING A BOILING POINTBETWEEN ABOUT 200* AND 275*C. AT 0.1 MM. HG.